The present invention relates to a latch assembly for a fireproof door lock and, more particularly, to a latch assembly with a safety device for a fireproof door lock for a door mounted in a passageway or panic exit, with top and bottom latches of the fireproof door lock retained in the latching positions during a fire to avoid expansion of the fire and smoke by avoiding opening of the door.
Fireproof door locks are generally mounted to fireproof doors in passageways or panic exits and generally include horizontal type latches and vertical type latches. Vertical type latches include a top latch and a bottom latch. The fireproof lock door should be remained in the closed position during a fire to avoid expansion of the fire or smoke. However, the parts of the fireproof door lock may deform due to the high temperature of the fire, such that the door can not be retained in the closed position. Specifically, the latch bolts of the top and bottom latches may be moved to the retracted, unlatching position due to deformation resulting from the heat of the fire. As a result, there is a risk of expansion of the fire and smoke if the door is opened.
Thus, a need exists for a safety device for a fireproof door lock in which the top and bottom latches of the fireproof door lock can be reliably retained in the latching positions during a fire.